Initial Stroke Analysis

Group 29: Helena Møller, Emma Christiansen, Casper Harreby, Frederik Holmstrup, and Laura Christiansen

Introduction

The International Stroke Trial v. 2 data

  • Assessing efficacy and safety of antithrombotic therapy compared to control.
  • Antithrombotic agents: Aspirin and subcutaneous Heparin.

Ischaemic stroke and treatments

  • Ischaemic stroke: Medical condition in which poor blood flow to a part of the brain causes cell death

Project Aim

  • Assessing effects of antithrombotics (heparin and aspirin) for recurrent ischaemic strokes

Methods

Raw data:

  • 19435 observations with 112 variables.

01_load:

  • Data has been loaded and saved in a tsv-file.

02_clean:

  • Global syntax of NA, and Y/N for binary variables.
  • Global syntax for the use of numbers 1-8 as to describe causes of death.
  • Correction of errors made when the data was collected.
  • Removal of column determined to be irrelevant.
  • Merging of columns for easier data analysis.
  • Data was split and re-joined into one.

03_augment

  • Groups created based on different treatments, and different doses of aspirin and heparin.
# 03_augment.qmd
# Calculating "body fat percentage" and "conicity index".
# Add new variables
diabetes_data <- diabetes_data |> 
  mutate(bin_sex = case_when(
                    sex == "male" ~ 1,
                    sex == "female" ~ 0
                  ),
         bfp = 1.39*bmi+0.16*age-10.34*bin_sex-9,
         waist_m = waist/100,
         height_m = height/100,
         ci = waist_m/(0.109*sqrt(weight/(height_m))),
         dm_status = case_when(
                      diagnosis == 0 ~ 1,
                      diagnosis == 1 & medication == 0 ~ 2,
                      diagnosis == 1 & medication == 1 ~ 3
         ))

Descriptive analysis

  • Observations/patients: 19,435
  • Variables: 98
  • Treatment groups: 6
[1] "Missing treatment group image"

Impact of treatment on subgroups

Models of the bla bla

Time of death after randomization

:::: {.columns} ::: {.column width=“50%”} - blabla - blabla

::: ::: {.column width=“50%”}

:::

Events during first 14 days

  • Patients receiving higher heparin doses and asprin are more frequent in cerebral bleed/haemorrhagic stroke group
  • Likewise, higher heparin doses and aspirin patients are more represented in patients with indicator of non-cerebral bleed
  • Patient group receiving no trial medication had more subjects with indicator of pulmonary embolism

Data visualization:

Kaplan Meier Plot after stroke:

Chi squared test of the treatment effect